One last letter definitely reminds me of
(yay for original compositions)The idea sounds sad though...and in the pic Twi looks surprised.
Also, watch out for a few proportional errors:
-head more rounded
-mane longer at the top
-letter and pen seem to be too large, not sure though
-hoof more rounded
I usually use navy blue mixed with violet for the mane, and for the highlights, I use ruby red and orchid. (Crayola pencil crayon colours by the way)
It's a good idea though.